Multiposition chairs are used in many areas. One use is found in the modern dental office, where the dental chair often includes mechanism for raising and lowering the chair seat and for tilting the chair forward and rearward. This allows the operator to position the chair and the patient for convenient operation by the dentist, and to another position more convenient for entering and exiting by the patient.
Explaining further, the chair is placed in a first position for ease of entry by the patient. After the patient is seated the dentist operates the chair to move the patient into a position appropriate for the dental procedure to be undertaken. Upon completion of the procedure, the chair is repositioned to allow the patient to exit the chair.
A primary consideration in such procedure is providing a control means which allows the operator to conveniently and precisely position and reposition the chair. It has been found that a foot switch connected to operating mechanism for the chair and situated near the chair is convenient for the operator.
As stated, such chairs generally include operating controls permitting selected raising and lowering of the chair and forward and rearward tilt of the chair. Further, operating mechanism often is included which allows certain preselected positions to be established in an electronic memory for the chair, whereby the closing of a single switch actuates operating mechanism in the chair to move the chair automatically to a selected preprogrammed position.
It would therefore be convenient for the operator to have two sets of independently operable switches. One set would be adapted to allow infinite variation of movement of the chair (such as raising and lowering and forward and rearward tilt) and the second set of switches would be operable to actuate the chair to shift automatically to selected preprogrammed positions.
Although it is desirable to have separate foot switch controls on a single unit, they must be placed so that they are adequately separated to prevent concurrent actuation by the user's foot. They also must be conveniently positioned and of a sufficiently small size that they are not an impediment in the floor area surrounding the chair.
A general object of the present invention is to provide a switch controller which is inexpensively constructed, convenient to use and which provides multiple switch controls for associated operating mechanism.
More specifically, an object of the invention is to provide a plurality of spaced apart pressure sensitive switches and a control pad with a plurality of contact points overlying the switches, each of which contact points is associated with an individual switch to define a contact pair therebetween. A fulcrum element is provided between adjacent contact pairs to inhibit simultaneous actuation of adjacent switches by their associated contact points.
A still further object of the present invention is to provide such a novel controller wherein the control pad is an elastomeric footpad secured at its periphery in a housing with the upper surface of the pad engageable by the foot of the user. The footpad has contact points on its underside to contact and actuate pressure sensitive micro switches disposed thereunder. A universal pivot mount is provided for the footpad to permit universal pivoting of the pad between actuating and nonactuating positions.
Another object of the present invention is to provide a novel foot switch for operating a patient chair which includes a pair of footpads each of which is operable to produce different operational movement of the chair. The footpads are mounted on a housing which has a central ridge region-and upper support surfaces which incline downwardly from opposite sides of the ridge region. One footpad is supported on one inclined surface of the housing, and the other footpad is supported on the opposite inclined support surface. Such construction permits the two footpads to be positioned rather closely together to provide a compact dual foot switch, yet provides a mode of separation between the two to inhibit user actuation of both at the same time.
A still further object of the present invention is to provide such a novel foot switch or controller which has a third switch mounted on the ridge region of the housing and a bumper projection extending upwardly from the ridge region adjacent the third button and intermediate the two previously mentioned footpads.
Yet another object of the invention is to provide a novel foot switch for use in operating a patient chair which includes a housing cover with a defined opening therein, and a footpad formed as an integral elastomeric member having a peripheral groove therein for receiving and gripping the edge margins of the opening in the housing. The footpad spans the opening in the housing to provide a full covering overlying internal switch mechanism to prevent contamination of the switch mechanism.
These and other objects and advantages will become more fully apparent as the following description is read in conjunction with the drawings.